AnsweredAssumed Answered

i.mx8m: Display content of MIPI DSI panel becomes disordered after upgrading to Yocto 2.4

Question asked by Richard Hu on Sep 10, 2018
Latest reply on Feb 18, 2019 by Dmitriy Falko



I encounter a strange problem on the display content of MIPI DSI panel after upgrading to Yocto 2.4(Rocko).


We have 5" inch (720x1280) MIPI DSI panel and it works pretty well on Yocto 2.2(Morty) on our custom i.mx8m board.


After we upgrade to Yocto 2.4, the display content becomes disordered, and the disordered pattern changes periodically.


We use exact same 4.9.88 kernel in buildroot and it doesn't have this problem.


So i suspect this problem might result from the weston compositor. It manipulates the display content via DRM or KMS periodically. It looks like that the bpp settings or resolution is changed periodically.


The situation is like:

When i boot into yocto, the display content looks like:

After 40~50 seconds, the pattern changes to:


It just keep changing the pattern like random every 40~50 sec.


I upload a video clip on youtube to let you understand this situation easily.

disordered pattern on MIPI DSI panel - YouTube 


Do i need to modify the settings in weston somewhere to fit in the panel we use?